The aim of the study was to assess the atmospheric and meteorological parameters for the control of blasting dust. Dust generated due to blasting at large surface coal mines causes air pollution in and around the mining area. The dispersion of blasting dust depends on prevailing atmospheric and meteorological conditions. A Sound Detection and Ranging (SODAR) was installed at the mine site to monitor atmospheric conditions in four seasons. Over 2000 sodar echograms were examined and classified into six categories as rising layers, thermal plume (free), ground based layer (spiky top), spiky top layer (clear weather), flat top layer (calm cold), and ground based stratified and multiple layers. Dot echo structures in the echograms were also observed during rainfall. From sodar echograms, unstable and stable periods were identified. Pasquill stability classes were evaluated by echograms and mixing heights. An automatic weather station was also installed at the site to monitor meteorological parameters as wind speed, wind direction, temperature, humidity, solar radiation and rainfall. Simple correlations as well as multiple regression analysis of meteorological parameters with mixing height show that solar radiation has strong influence on mixing height. The nearby villages that are likely to be affected by blasting dust can be protected by planting trees perpendicular to the wind direction as indicated by windrose diagrams. Dispersion factors, the product of mixing height and wind speed, were calculated for all the seasons. It was suggested that blasting should be conducted during the period when the dispersion factor is maximum so that the impacts of blasting dust on the environment can be minimised.
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